#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>

int main()
{
	int sum =0 , i = 1;
	for (; i <= 100; i++)
	{
			if(i / 10 == 9) sum++;
			if(i % 10 == 9) sum++;
		}
	printf("%d\n", sum);
	return 0;
}